
class Solution {
    public:
        int maxProfit(vector<int>& prices, int fee) {
            int n = prices.size();
            vector<vector<int>> dp(n,vector<int>(2));
            //dp[i][0]表示第i天结束后我还持有股票
            //dp[i][1]表示第i天结束后我不持有股票
            dp[0][0] = -prices[0];
            dp[0][1] = 0;
            for(int i = 1 ; i < n ; i++){
                dp[i][0] = max(dp[i-1][0],dp[i-1][1]-prices[i]);
                dp[i][1] = max(dp[i-1][0]+prices[i]-fee,dp[i-1][1]);
            }
            return max(dp[n-1][0] , dp[n-1][1]);
        }
    };